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排序方式: 共有247条查询结果,搜索用时 12 毫秒
31.
Dave VP; Keefe R; Berger MA; Drbal K; Punt JA; Wiest DL; Alarcon B; Kappes DJ 《International immunology》1998,10(10):1481-1490
CD3delta-deficient (delta degrees) mice are defective in alphabeta T cell
development. Here we explore the capacity of TCR-CD3 signaling complexes
expressed on delta degrees thymocytes to mediate the following functional
outcomes in response to antibody cross-linking: (i) the transition from the
CD4-CD8- to CD4+CD8+ stage, (ii) the transition from the CD4+CD8+ to
CD4+CD8- or CD4-CD8+ stages and (iii) the induction of apoptosis. We
provide evidence that CD3deltaepsilon complexes are dispensable for
mediating the anti-CD3-mediated CD4-CD8- to CD4+CD8+ transition. On the
other hand, CD3delta is critical at the CD4+CD8+ stage. We demonstrate that
CD4+CD8+ thymocytes from delta degrees mice, unlike delta degrees CD4-CD8-
thymocytes and wild-type CD4+CD8+ thymocytes, require prolonged or
consecutive stimuli to elicit functional responses. Depending on the nature
of the secondary stimulus, delta degrees thymocytes can be induced to
undergo apoptosis or preferential maturation to the CD4-CD8+ stage. Taken
together these results indicate that the signaling capacity of the TCR-CD3
complex is noticeably altered in the absence of CD3delta. The essential
role of CD3delta at the CD4+CD8+ stage of development correlates with the
onset of TCRalpha rearrangement, consistent with a critical structural
and/or functional relationship between CD3delta and TCRalpha.
相似文献
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33.
A 22 year old male presented with symptoms of diffuse muscle pain and multiple abnormal laboratory findings that were eventually attributed to tropical myositis. Computed tomography scan was more reliable than ultrasound and served as a guide to needle aspiration and pathologic diagnosis. 相似文献
34.
Triple-balloon dilation (TBD) of a variety of luminal structures has been successfully, though infrequently, used. A mathematical model is presented for the selection of balloon sizes, and equations and tables are derived that allow the user to estimate more accurately the size of balloons needed for TBD of structures with large lumina. With TBD, an approximately circular lumen can be formed. Also, TBD allows smaller, higher-pressure balloons to be used instead of single, low-pressure, large balloons. However, multiple puncture sites may be required for TBD. 相似文献
35.
Embolization of renal carcinoma 总被引:7,自引:0,他引:7
36.
Perez RM Ferreira AS Medina-Pestana JO Cendoroglo-Neto M Lanzoni VP Silva AE Ferraz ML 《Journal of clinical gastroenterology》2006,40(5):444-448
BACKGROUND: The eventual impact of immunosuppression on the natural history of hepatitis C virus (HCV) infection in patients with end-stage renal disease (ESRD) is still unknown because of the lack of comparative data for HCV-infected patients with ESRD and renal transplant patients. The aim of this study was to compare the biochemical and histological characteristics of chronic HCV infection in renal transplants patients and ESRD patients undergoing hemodialysis. METHODS: Thirty-eight renal transplant patients and 38 ESRD patients undergoing hemodialysis who were chronically infected with HCV and were matched for gender, age at infection, and estimated time of infection were included in the study. The groups were compared regarding laboratory and histological variables. RESULTS: Renal transplant patients showed similar alanine aminotransferase and higher gamma-glutamyltransferase levels (P = 0.05) when compared with ESRD patients. Comparative analysis of histological variables revealed a higher proportion of cases with septal fibrosis (P = 0.04) and confluent necrosis (P = 0.01) among transplant-recipient patients. No difference between groups was observed regarding the intensity of portal and periportal inflammatory infiltrates. Steatosis was more prevalent among transplant-recipient patients (P < 0.001). There was no difference between groups regarding the prevalence of lymphoid aggregates or bile duct injury. CONCLUSION: Renal transplant patients had a larger proportion of cases with septal fibrosis and confluent necrosis than did ESRD patients, suggesting that renal transplantation might modify the natural history of hepatitis C in ESRD patients, leading to a more aggressive liver disease. 相似文献
37.
L Balestrini C Fleishman L Lanzoni J Kisslo A Resai Bengur S P Sanders J S Li 《Journal of the American Society of Echocardiography》2000,13(3):171-176
We evaluated the ability of real-time 3-dimensional (RT3D) echocardiography to diagnose congenital heart defects and its potential for presenting structural abnormalities in novel views. Seventy-five patients with suspected congenital heart defects were examined with the use of RT3D echocardiography. Images were reviewed off-line as multiple slices of the raw data or as volume-rendered images by a blinded observer. Diagnoses made from blinded review of the RT3D images were compared with the clinical report of the 2D echocardiogram obtained at the same visit. Real-time 3D echocardiography identified all structural abnormalities except for small atrial septal defects in 2 patients and coronary artery anatomy in D-transposition of the great arteries. Less than 5 minutes were needed to acquire RT3D images in all cases, and sedation was never required. Unique region-oriented views obtained from the 3D data set can be acquired quickly and have the potential to enhance understanding of complex cardiac anatomy. 相似文献
38.
Vinceti M Malagoli C Fiorentini C Longo C Crespi CM Albertini G Ricci C Lanzoni A Reggiani M Virgili A Osti F Lombardi M Santini M Fanti PA Dika E Sieri S Krogh V Seidenari S Pellacani G 《Nutrition and cancer》2011,63(4):506-513
The possibility of an inverse association between vitamin D and risk of cancer and, in particular, of cutaneous malignant melanoma has been suggested, but results of epidemiologic studies are still conflicting. We examined the relation between dietary vitamin D intake and melanoma risk through a population-based case-control study (380 cases, 719 controls) in a northern region of Italy, a country with an average vitamin D intake lower than that in northern Europe or the United States. We assessed average daily intake of vitamin D from foodstuffs using the European Prospective Investigation into Cancer and Nutrition (EPIC) semiquantitative food frequency questionnaire. In this population, levels of vitamin D intake were considerably lower than those observed in recent U.S. studies. We found an inverse relation between dietary vitamin D and melanoma risk in the sample as a whole, in both crude and adjusted analyses. In sex- and age-specific analyses, this association appeared to be stronger among males and among older subjects. These findings suggest that, at the relatively low levels of intake observed in this sample, an inverse relation between dietary vitamin D and risk of cutaneous malignant melanoma may exist. 相似文献
39.
40.
BACKGROUND: Exposure to Aspergillus fumigatus allergens results in enhanced total serum IgE and peripheral blood eosinophils in mice. The associated pulmonary inflammation and immunologic responses are comparable to those detected in human allergic bronchopulmonary aspergillosis. Allergen-induced cytokines are thought to regulate the inflammatory and immune responses in these animals. METHODS: In the present study, we exposed C57BL/6 and BALB/c mice to A. fumigatus antigen. Both wild-type and IL-4 knockout phenotypes of animals of both strains were used. Some animals were also treated with anti-IL-5 or anti-IFN-gamma. Total serum IgE, Aspergillus species IgG subclass, peripheral blood eosinophils, and lung histology were studied. RESULTS: The results demonstrate similar lung inflammation in all wild-type and IL-4-/- animals exposed to A. fumigatus antigen. Similarly, in spite of the diverse immune response produced by the anticytokine treatment, no major differences were detected among any of the animal groups studied. CONCLUSIONS: It can be concluded that A. fumigatus exposure in an immunologically unaltered host is predominantly of a Th2 type, and that depletion of the Th2 cytokine leads to a similar lung inflammation but with a characteristic Th1 response, suggesting that the pathogenesis of allergic aspergillosis is the result of multiple induction pathways. 相似文献